The Department for Infrastructure(DfI) is introducing a green filter arrow at Orritor Road junction in Cookstown over the next fortnight.
It follows confusion amongst motorists using the busy junction with claims that there were several 'near misses'.
A DfI spokesperson said: "To reduce traffic delays at the busy Westland Road/Orritor Road/Morgans Hill Road Junction the Department for Infrastructure recently installed a new traffic light signaling sequence to help optimise traffic flow along the Morgans Hill and Westland Road and thereby reduce delays.
"The upgraded signals have greatly improved the flow of traffic through this junction and shortened queues on the Westland Road and Morgans Hill Road.
"However, since its implementation we are aware that the right turn from Morgans Hill Road onto Orritor Road has presented difficulty for some drivers. To address this, DfI has now agreed to introduce a green filter arrow for those turning right onto Orritor Road. This will be implemented over the next few weeks.
"As with any changes to road junction layouts there may be a settling in period as people get used to the new arrangement. The Department would advise all road users to approach the junction with due care and attention and to abide by the signs and white lines.”